This invention relates generally to walking aids, and more particularly, to a crutch or cane constructed to distribute a person's weight to minimize stress on the user's wrist.
Walking aids have evolved over time from simple wooden sticks to specialized canes and crutches to assist persons with temporary or chronic disabilities in walking. Most canes employ a straight vertical support member which contacts the ground and a generally horizontal hand grip attached to the vertical member. Persons with longer-term disabilities usually use a crutch of the "Canadian" type, which has an extension to the vertical member to which is mounted a cuff assembly which gives additional support and control to the forearm of the user.
There are a number of inherent problems with crutches and canes, and particularly with crutches for long term use. For one thing, much of the weight that would otherwise be supported by the legs must be supported by the arms of a crutch user and, as a result, the hand and wrist joints experience a great deal more stress than was intended for those joints. Most prior art crutch designs force the hand to be held in a horizontal position which places uneven weight on the wrist joint, leading to chronic pain and certain types of joint degeneration in long term users.
In addition, most Canadian style crutches and canes use a straight shaft or a shaft which is straight in the forward direction to contact the ground. This straight shaft transfers the impact shock of the shaft striking the ground directly to the wrist and arm of the user, further increasing the stress on the wrist and hands.
In addition, most crutches are assembled from lightweight metal tubing and have some adjustable parts which allow the crutches to be modified to fit users of different heights and weights. However, for most crutch users, once the crutch is fitted, it is never adjusted again. The adjustment mechanisms, however, which are relatively complex, continue to contribute significantly to the weight of the crutch and are usually the first point of mechanical failure in the crutch. In addition, the typical attachments and adjustments to metal crutches are usually noisy and contribute to the discomfort of the user.
Most crutches and canes also have conventional rubber foot grips at the bottom of the shaft with grooves to engage and grip the ground. However, these relatively small pads have treads located only on the bottom surface which provide full stability only when the crutch is perpendicular to the ground. There is reduced gripping action with these foot grips when the crutch is angled at the beginning or end of a walking stride.
Although the prior art has attempted to provide solutions for some of these problems of long term crutch users, there has been a longstanding need for a lightweight crutch which has no mechanical parts, which redistributes the weight of the user in an ergonomic manner, which reduces the impact forces of the crutch striking the ground and which provides stability and balance through the full range of a walking motion.